The demand for faster and smaller microelectronic devices is driving continual shrinks of microelectronic architectures. Such microelectronic architectures form the electronic circuits of semiconductor devices. Semiconductor devices are manufactured on silicon wafers using a process of adding layers and selectively removing parts of the layers. The wafers are cut into individual dies upon the completion of the manufacturing process. Each individual die includes a semiconductor device having a core area, where logical computations are made.
Individual dies are not typically directly integrated into electronic devices, such as, for example, cell phones. Thus, semiconductor devices typically include at least one I/O (input/output) interface circuit enabling communication with other devices. I/O circuits, or cells, are typically arranged at the periphery of each individual die. This peripheral area may be referred to as the I/O ring.
In the manufacture of semiconductor devices, the selective removal of layers is enabled by a process called lithography. Through lithography, ever smaller features are imaged on the wafer surface. Increasingly smaller gate transistors are required to satisfy the increasingly higher speed requirements of microelectronic devices. However, as just one example, factors such as the wavelength of light place limitations on minimum resolvable feature sizes. Further, semiconductor devices and their I/O rings are becoming more complex due to their increasing compaction of functionality. Consequently, improvements to lithographic processes are continually sought to enable production of continually shrinking features. It follows that it is desirable to reduce semiconductor processing variation. Therefore, a need exists for improved methods for semiconductor devices, improved semiconductor devices, and improved lithographic patterning devices.